Carburetor



July 5, 1932. L. HUBER ET AL GARBURETOR Filed Oct. 20. 1930 2 Sheets-Sheet 2 carburetor Patented July 5, 1932 PATENT OFFICE LUDWIG HUBER AND RICHARD DISTEL, OFDETROIT, MICHIGAN CARBURETOR Application filed October 20, 1930. Serial No. 489,834.

The invention relates to improvements in Vaporizers and particularly to an improved carburetor for internal combustion engines.

An object of the invention is to provide a for an internal combustion engine with a mixing chamber having a centrally arranged fuel inlet to insure complete vaporization of said fuel.

Another object is to provide an improved carburetor with means to regulate in unison the volumes of air and fuel admitted to the mixing chamber.

Another object is to provide improved rotatable means to control the volume of vaporized fuel discharged into the manifold of an internal combustion engine.

Another object is to provide a single control for regulating the volumes of air and fuel admitted to the mixing chamber of a carburetor and the volume of vaporized fuel discharged therefrom.

Another object is to provide a carburetor of the character referred to with means for independently regulating the volume of air admitted to the mixing chamber.

Another object is to provide an improved carburetor of the character described which is compact and easy to assemble, easy to ad just, and which is not expensive to manufacture.

The foregoing and such other objects of the invention as will appear hereinafter as the description proceeds, will be more readily understood from a perusal of the following specification, reference being had to the accompanying drawings, in which:

Fig. 1 is a vertical longitudinal central sectional view through the improved carburetor, showing the parts in the position assumed while the engine is idling or operating at a low rate of speed. v

Fig. 2 is a view similar to Fig. 1, showing parts in the position assumed while the engine is operating at increased speeds.

Fig. 3 is a sectional plan view, taken on line 33 of Fig. 1.

Fig. 4 is a horizontal sectional on line 4-4 of Fig. 1.

Fig. 5 is a sectional view, taken substantially on line 55 of Fig. 2.

view, taken proved carburetor said Fig. 6 is a fragmentary sectional view,

adjusting collar in elevation.

Fig. 7 is a longitudinal central sectional view, in perspective, of the mixing chamber. Fig. 8 is a perspective View of the rotatable throttle control or cam member.

' Referring to the drawings in detail, the impreferably comprises a housing 11 formed of two sections 12 and 13, machined to insure perfect fitting, and held together by suitable screws 14. The free end of the housing portion 12 is provided with the usual external flange 15, for receiving bolts 16 by which the carburetor is secured to the usual intake manifold 17 of an internal combustion engine (not shown). The housing section 12 is provided with a central longitudinal bore for receiving a mixing chamber 18, in the form of a sleeve, which is valve 26. The air valve 26 is adapted to have a free sliding fit within the bore 25, and is normally urged downwardly by a suitable spring 27 mounted between a flange 28 on valve member, and a shoulder 29 provided in the longitudinal bore 25.

Air is admitted into the mixing chamber '18 through an opening 31 communicating with the annular recessed portion 24. To enter the mixing chamber, the incoming air must pass through the annular space between the flared end 23 of said chamber and the substantially conical end 32 of the air valve 26. It can readily be understood that the volume of air admitted to the chamber 18 can be regulated and controlled by Varying the chamber vent fuel from flowing therefrom. The nipin a cylindrical casing 34 secured over the end of the housing section 13 by screws 35. Mounted for reciprocable rotation in casing 34 and rigidly conected with the throttle lever 33 is a rotatable cam member 36. A recess 37 is provided in one end of the cam member 36 to provide an annular shoulder 38 having diametrically opposed cam surfaces 39. A pair of diametrically opposed cam surfaces 40, similar to cam surfaces 39 but somewhat larger, are provided on the other end of the cam member 36, which also is recessed.

Suitable ball bearings 41 are arranged between the cam member 36 and the air valve 26. As the air valve 26 is urged downwardly by the spring 27, said valve is yieldably held against the ball bearings, which in turn are maintained in close contact with the face of the cam member. It can readily be understood that manipulation of the throttle lever 33 to effect partial rotation of the cam member 36, moves the cams beneath or away from the rollers 41, thereby effecting longitudinal movement of the air valve 26 to decrease or increase the cross-sectional area of the annular space between the flared surface 23 and the valve end 32 to regulate the volume of air admitted to the mixing chamber Extending longitudinally into the end wall 42 of the casing 34, and through the rotatable cam member 36, and the air valve 26, is a tubular stem or fuel inlet 43, having a longitudinal passageway 44 extending therethrough. A fitting 45 on the enlarged extending end of the stem 43 provides a connection for the usual fuel line leading from the supply tank (not shown). A shoulder 46 is provided on the stem adjacent its enlarged end for receiving thereover a collar 47, which is securely held in place by a nut 48. The collar is adapted to have a free sliding fit within the recessed end 37 of the rotary cam member 36.

Suitable recesses or pockets 49 are rovided in one face of the collar 47, and aliall 50 is arranged in each recess for co-operative engagement with cams 39 on the shoulder 38 of cam member 36. A coil spring 51, arranged between the end wall 42 of the cylindrical shell 34 and the collar 47, tends to urge said collar and the balls against the shoulder 38. The reduced end 52 of the stem 43 extends through the air valve 26 and has a bore 53 of reduced diameter therein, whereby, fuel entering the stem 43 through the fitting 45 may flow through the longitudinal bores 44 and 53 substantially into the center of the mixing chamber 18. However, when the engine is not operating, or idling, the tapered end of a nipple 54, threadingly mounted in a spider 55 formed integral with the mixing 18, extends into the bore 53 to preple 54 is provided with a longitudinal port 56 having a tapered outlet end or valve seat to normally receive the tapered end of a valve stem 57. With the valve stem 57 closing the port 56 in the nipple 54 and said nipple in engagement with bore 53 no fluid can pass into the mixing chamber.

The valve stem 57 is mounted in a sleeve 58 which extends into the mixing chamber 18 from a suitable shutter 59 fixedly secured in the open end of the housing section 12 by a set screw 61. Mounted upon the threaded end of the valve stem 57 and adapted normally to be held against the fixed shutter 59, is a movable shutter 62. A spring 63, mounted within the sleeve 59, holds said shutters together and normally retains the tapered end of the valve stem 57 in engagement with the port 56 of nipple 54. Thus, with the two shutter members closely held together in closed position, the outlet from the mixing chamber 18 is closed, and no vaporized fuel or air can pass into the manifold 17.

Immediately upon starting of the motor, the shutter 62 is raised, against the act-ion of spring 63, by the vacuum created in the manifold 17 to draw the tapered valve stem 57 away from the port 56 and permit a small quantity of fuel to flow into the mixing chamber. Fuel entering chamber 18 through this port is spread upwardly outwardly and towards the side walls of said chamber to be mixed with air entering around the stem 43 through the opening at- 31. This valve will remain open as long as the motor is idling; that is, running at a low rate of speed.

To vary the idling speed of the motor, it is necessary to increase the volume of fuel admitted through the port 56. To this end a suitable thumb control 64 is journaled in the housing section 12 and extends through the wall of the mixing chamber 18, as shown. An eccentric 65, engages between spaced lugs 66 on an adjusting sleeve 67, which is mounted between the end of the fixed sleeve 58 and the enlarged tapered end of the valve stem 57. The eccentric is carried on the innermost end of the thumb control stem 68. One edge 69 of the adjusting sleeve 67 is formed irregular to provide a cam surface for co-operation with a similar surface provided on the edge of sleeve 58. Manipulation of the thumb control 64 effects partial rotation of the adjusting sleeve 67 and because of the irregular edge thereon, the amount of opening of the valve is regulated.

To increase the speed of operation of the engine, the throttle lever 33 is moved, and by reference to Fig. 2, it will be noted that said movement efiects a change in the relative positions of the stem 43, air valve 26, valve stem 57 and shutter 62. Manipulation of the throttle lever 33 effects partial rotation of the rotary cam member 36, whereupon the cams 40, co-operating with ball bearings 41, are moved to such a position that the bearings and likewise, the air valve 26 move downwardly by action of the spring 27. This movement of the air valve increases-the cross sectional area of the annular space between the flared end 23 of the mixing chamber and the end 32 of the air valve, thus allowing an increased volume of air to enter the mixing chamber.

The volume of fuel admitted to the mixing chamber is also increased by the longitudinal movement of the fuel inlet stem 43 against the action of spring 51. Movement of the stem 43 is effected by co-operative engagement of the ball bearings 50 with the cam- .surfaces 39 on the rotary cam member 36. Downward movement of the stem 43 moves the reduced bore 53 thereof out of engagement with the tapered end of nipple 54, and the fuel may now enter the mixing chamber without passing through port 56. However, this port is now closed by action of spring 63 upon the valve stem 57, because movement of the cam member 36 effects a similar movement of shutter 62, through an arm connection '71, and the plurality of openings 7 2 in said shutters align or partially align to open the outlet and break the partial vacuum in the mixing chamber. In this manner the partial vacuum which held the movable shutter 62 and valve stem 56 elevated becomes lost and the vaporized fuel in the mixing chamber passes through the aligned openings 72 into the manifold 17 Adjustment of the volume of air admitted to the chamber 18, relative to the volume of fuel admitted, is readily attained by providing independent adjustable means for varying the cross-sectional area of the annular space between the flared end 23 of the mixing chamber and the end 32 of the air valve. To this end, an adjusting plate 7 3 is mounted between the rotary cam member 36 and the air "alve 26, said plate having suitable openings for receiving and retaining the ball bearings 41 in place. An arm 74 formed integral with the plate 73, extends through the wall of shell 34 whereby, upon manipulation of said arm, partial rotation is imparted said plate to change the position of the ball bearings 41 relative to cams 40. By this means the ball bearings 41 normally may be positioned on the highest point of the cam members 40, at which time the area of the air inlet is reduced to a minimum size.

A reduction nipple 7 5 preferably is arranged in the fuel inlet passageway 44 to restrict the fiow of fuel into the mixing chamber. This reduction may be of any size or it may be formed integral with the passageway, if desired. 7

It can readily be understood that the improved carburetor aflords complete vaporization and control of the fuel entering the mixing chamber because the fuel is completely disintegrated upon being discharged from both thevolume of air and fuel is regulated in u unison, also is a decided improvement over known carburetors, most of which utilize a float for controlling the supply of fuel and employ no automatic air control means.

Although an examplary form of the invention has been illustrated in the accompanying drawings and described in detail in the foregoing speciflcation, it is to be understood that the improved vaporizing device may incorporate such modifications and variations in 7 detail structure as will remain within the spirit of the invention and the scope of the appended claims.

We claim:

1. A fuel vaporizing device for an internal combustion engine, comprising, in combination, a mixing chamber having an outlet, a fuel inlet and an air inlet communicating with said mixing chamber, a valve in said fuel inlet, a shutter in the said outlet operatively connected to said valve, and yieldable means to maintain said shutter and valve closed while the engine is idle, said shutter being actuated upon the starting of said engine to open said valve.

2. A fuel vaporizing device for an internal combustion engine, comprising, in combination, a mixing chamber having an outlet, a valve controlled fuel inlet communicating with said mixing chamber, a valve in said outlet operatively connected with the fuel valve, positive means to hold said valves closed while the engine is idle, said means being yieldable to allow opening of said valves while the engine is operating at a low rate of speed to admit fuel into said mixing chamber.

3. A fuel vaporizing device for an internal combustion engine comprising, in combinaton, a mixing chamber, a fuel inlet and an outlet communicating with said chamber, a closure shutting said inlet while the engine is idle,means in said outlet adapted to open said closure while the engine is operating at a low rate of speed, and means to adjust said closure to regulate the volume of fuel admitted to said chamber.

' 4. A fuel vaporizing device for an internal combustion engine comprising, in combination, a mixing chamber, a fuel inlet and an outlet communicating with said chamber,

means closing said inlet while the engine is idle, means adaptedto open said inlet while the engine is operating at a low rate of speed,

and manually operable means for increasing the operating speed of said engine, said means closing said inlet and opening an aux iliary fuel inlet provided in said chamber.

5. In a fuel vaporizing device for an internal combustion engine, in combination, a mixing chamber, a fuel inlet passageway communicating with said chamber, valves in said passageway adapted to close said fuel inlet while the engine is idle, vacuum actuated means for opening one of said valves to admit a small quantity of fuel into said cham- 35 her while the engine is operating at av low rate of speed, and manually operable means to open the other valve and effect closing of said one valve to increase the operating speed of said engine.

6. A fuel vaporizer for an internal combustion engine comprising, in. combination, a body having a mixing chamber therein, a fuel inlet and an air inlet communicating with said chamber, automatic means for regulating the volume of fuel admitted to said chamber while the engine is operating at a low rate of speed, an auxiliary fuel inlet communicating with said chamber adapted to be closed while said engine is oper ting at a low rate of speed, means for rendering said automatic means inoperative and for opening the auxiliarv fuel inlet to increase the volume of fuel admitted to said mixing chamber, and said means increasing the size of i 35 said air inlet whereby an increased volume of air is admitted to the mixing chamber to insure vaporization of the fuel.

7. A fuel vaporizer comprising a body having a mixing chamber therein, an air inifio let and a fuel inlet communicating with said mixing chamber, means to vary the volume of fuel admitted to said mixing chamber, said means comprising a manually operable rotatable cam member, and means actuated by 74-0 said cam member to vary the volume of air admitted to said mixing chamber.

8. A fuel vaporizer comprising a body having a mixing chamber therein, an air inlet and a fuel inlet communicating with said mixing chamber, means to vary the volume of fuel admitted to said mixing chamber, said means comprising a manually operable rotatable cam member, and yieldably mounted reciprocable means actuated by said cam member to vary the volume of air admitted to said mixing chamber.

9. In a fuel vaporizer, a mixingchamber, a fuel inlet comprising a tubular stem, a nipple fixed in said-chamber normally seating in the end of saidstem, a valve on said nipple, means for opening said valve to admit fuel --into said chamber, rotatable means to efiect closing of said valve, said means actuating to move said stem from said nipple to admit fuel 7 into the mixing chamber, and an air inlet in said mixing chamber having means operable by the rotatable means for regulating the volume of air admitted to said mixing chamber.

10. In a fuel vaporizer, a mixing chamber,

a fuel inlet comprising a tubular stem, a nipple fixed in said chamber normally seating in the end of said stem, a valve on said nipple, manually operable means for adjusting said valve,vacuum actuated meansfor opening said valve to admit fuel into said chamber, means for rendering said vacuum actuated means inoperative to efi'ect closing of said valve, said means co-operating with said stem to move it from engagement with the nipple to admit fuel into said chamber when the valve is closed, an air inlet in said chamber, and means operable by the valve closing means for regulating the volume of air admitted to said mixing chamber.

11. A fuel vaporizer having a substantially cylindrical mixing chamber, an air inlet communicating with said chamber, a fuel inlet comprising a tubular stem extending into said chamber, said tubular stem being arranged on the longitudinal axis of said chamber, a valve in the chamber on the inner end of said stem, and means for opening said valve whereby fuel is discharged substantially in the center of said chamber to effect complete disintegration and vaporization of said fuel.

12. In a carburetor for an internal conibustion engine, a mixing chamber having an air inlet, a fuel inlet centrally arranged in said chamber, a nipple in said fuelinlet hav ing a valve seat therein, a valve stem adapted to co-operate with said seat to prevent a flow of fuel into said chamber, and means actuated by the vacuum created upon operation of said engine at a low rate of speed for maintaining said valve stem removed from the seat whereby afine substantially conical spray of fuel is discharged through the nipple into said mixing chamber and vaporized.

In testimony whereof we affix our signatures at 3400 Union Trust Building, Detroit, Michigan.

LUDVVIG HUBER. RICHARD DISTEL. 

